JPS63180908A - Multiple-optical fiber aggregate - Google Patents

Abstract

PURPOSE:To improve image transmittability and resolution by forming multiple optical fibers to an approximately rectangular sectional shape of the outside circumference and providing rugged shapes reflecting the piling arrangement structure of light transmittable island components to the respective sides thereof. CONSTITUTION:The sectional shape of the arrangement structure in which the island components 2 forming light transmission bodies of the core-cladding structure having the approximately rectangular sectional shapes are piled in sea components 3 up to the outside circumferential part has the approximately rectangular shape. The multiple optical fibers 1, the respective sides of which have the rugged shapes reflecting the rugged shapes of the optical fibers arranged in the piled state are integrated in such a manner that said rugged faces engage with the end face of the multiple-optical fiber aggregate, by which this multiple-optical fiber aggregate is constituted. The fibers are particularly so arranged that the resolving power by a standard line pattern is >=2 line pairs/mm. The plastic multiple-optical fiber aggregate which can transmit sharp images with high resolution is thereby obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a plastic multi-fiber conduit having high resolution, toughness, and extremely bright transmission image power.

[Conventional technology]

Multi-optical fibers, which are made by arranging glass optical fibers with a fiber diameter of 200 μm or less into bundles with good alignment and joining both ends with a bonding agent, can transmit original images, so they are used in gastrocameras and other applications. Its use as an image guide is mainly being promoted in the medical device field.

However, glass optical fibers have poor toughness, so
If used as an image guide and repeatedly bent and bent, the optical fiber will break relatively easily during use and lose its image transmission properties, making it easy to lose its characteristics as an image guide. The repair techniques also require extremely sophisticated techniques.

In the past, development of plastic image bundles that are less likely to cause breakage accidents during use has been progressing;
-39505 publication or US Patent Publication No. 355663
No. 5 discloses an invention related to gelastec yarn multi-source fibers.

[Problem that the invention attempts to solve]

However, as shown in these publications, in the conventionally developed plastic image bundles, the shape of the light transmitting component arranged as an island component is a polygonal shape ranging from a square to an octagon. Because the cross-sectional area of the island components in the fiber varies widely, or because it is not possible to increase the density of the island components in a single multi-optical fiber, there are still many problems before it can be used as an image transmission medium that can transmit all clear images. It is desired to develop a plastic-based image bundle that can contain dots and transmit even clearer, higher-resolution images.

[Means for solving problems]

Therefore, the inventors of the present invention have completed the present invention as a result of studies aimed at developing a plastic multi-optical fiber assembly that can transmit clear, high-resolution images without the above-mentioned difficulties.

The gist of the present invention is to provide a core having a substantially circular cross-sectional shape.
An arrangement of original fibers in which the island component forming the sheath-structured optical transmission body is stacked in bales up to the outer periphery in the sea component, and the cross-sectional shape is approximately rectangular, and each side of the fiber is stacked in bales. It is a multi-optical fiber assembly in which multi-optical fibers having a concavo-convex shape are assembled so that the concavo-convex surfaces are interlocked with the end face of the multi-optical fiber assembly, and in particular, the resolution according to the standard line pattern is 2 line pairs. The plastic multi-optical fiber assembly is characterized in that it is arranged so as to have a DI of /3 DI or more.

The plastic optical fiber assembly of the present invention will be explained below with reference to the drawings.

Figure 1 is a cross-sectional view showing an example of the plastic multi-optical fiber used in the present invention), in which +11 is the plastic multi-optical fiber of the present invention, (2j is a pixel responsible for image transmission). The optical transmission island component that constitutes the
(3) is the sea component.

As shown in Section 1, in the plastic multi-optical fiber used in the present invention, the cross-sectional shape of the island component is approximately circular, and the island component is arranged in a bale-stacked arrangement structure in the sea, extending to the outer periphery of the two islands. The arrangement is not distorted, therefore, the outer circumferential Vr surface Jl shape of this multi-optical fiber is approximately rectangular, and there is a large Lfjet in that it has an uneven shape that completes the stacked structure of island components. ing. As the outer peripheral cross-sectional shape of the multi-optical fiber becomes distorted, for example, as the cross-sectional shape approximates a circular cross-sectional shape, the arrangement of the optical transmission islands and island components changes to a stacked arrangement structure near the center of the cross-section of the multi-optical fiber. However, at the outer periphery, the arrangement structure is disrupted, the cross-sectional shape of the island component is also deformed into a polygonal shape, and the cross-sectional area of the six island components becomes intense, and the clarity of the image transmission itself is affected. It disappears.

In addition, in order to make a multi-optical fiber assembly with a high pixel count, it is necessary to assemble a multi-optical fiber assembly with a circular cross-section. I can't. US special fi
With multi-optical fibers as shown in No. 3556635, it is difficult to form a uniform multi-optical fiber assembly;
The disadvantage is that it is difficult to create a multi-optical fiber assembly with relatively high resolution.

Further, the island component must form a core-sheath structure consisting of a core for transmitting light and a sheath for improving the transmission. When the structure of the island component existing in the sea component does not form a core-sheath structure, when white light is transmitted,
When one set of black and white lines is considered as one line pair, as the number of lines (1s+s) increases, the boundaries between black and white lines become difficult to read. It cannot be made into fiber.

The resolution line pair/WX used in the present invention is measured as follows.

A resolution test target (USAF 1951) is installed at one end of the multi-optical fiber or assembly thereof and is illuminated with light from a light source to transmit a test pattern. A condensing lens and an image receiving surface are installed at the other end of the multi-optical fiber, and the transmitted test pattern is discriminated.

Alternatively, a photographic film may be placed on the image receiving surface to record the transmitted test pattern.

The arrangement density of island components defined in the present invention is 2 line pairs/g.
It is necessary that it is above. This line pair density is 2
Is image transmission with good resolution possible when the line pair/m is less than that? It is difficult to carry out, and in the present invention, it is usually 5 to 30
It is preferable to set it in the range of line bear/mm. When the number of line pairs increases beyond 60 line pairs/ws, the array structure of the island component in the ocean component is disturbed, its cross-sectional shape is deformed, and the influence of lamination gaps becomes large, resulting in a decrease in resolution. This value should not be set to an abnormally high value, as this may cause

Specific examples of plastics for forming the core component and sheath component of the multi-optical fiber of the present invention include the following.

Polymethyl methacrylate (n=1.49) and a copolymer based on methyl methacrylate (n=1.49).
47A-1,50), polystyrene (n=1.58) and styrene-based copolymers (n=1.50)
~t, 58), styrene acrylonitrile copolymer (n=1.56), poly4-methylpentene 1 (n=1
．． 46), ethylene/acetic acid copolymer (n = 1
．． 46A-1,50), polycarbonate (n=1.5
0 to 1.57), polychlorostyrene (n=1.61
), polyvinylidene chloride (n=1.65), polyvinyl acetate (n=1.47), methyl methacrylate/styrene, vinyltoluene or a-methylstyrene/maleic anhydride ternary or quaternary copolymer (n= 1
．． 50 to 1.58), polydimethylsiloxane (n=1
．． 40), polyacetal (n = 1.48), polytetrafluoroethylene (n = 1.55), polyvinylidene fluoride (n = 1.42), polytrifluoroethylene (
n = i, 40), perfluoropropylene (n
= 1.34), oyo c)' These binary or ternary copolymers of heptadated ethylene (n = 1j 5S1.40
), polyvinylidene heptadide/polymethyl methacrylate blend polymer (n=1.42 to 1.46),
A polymer whose main component is a fluorinated ip acrylate represented by the general formula (H2-C(OH3)I:1oORf, where Rf: (OH2)m (CF2)nF (n = 1
．． 37-1.40), Rf: (CH2)m(CF2
) nH (n = 1.37 Sl, 42), Rf:C
H(CF3)2 (n = 1.38), Rf: C
(CF, ), (n=1.56), Rf: CH20
F20HF CF, (n = 1.40), Rf
: CHCF(OF,)2 (n = 1.37), and their fluorinated methacrylate copolymers (n = 1
．． 36-1.40), and these fluorinated methacrylate and methyl methacrylate copolymers (n=1j 7
H1.45), general formula 〇H2=GH-00OR
A polymer whose main component is fluorinated acrylate represented by 'f, where R'f: (OH2), (CF2)
nF (n=1.37 to 1.40), R'! : (C
H2)! , 1(OF2)nH(n = 1.37S1.4
1), R'r: 0H20F2GHF 0F3(n
=1.41), R'f: 0R(OF, )2(n=1.
38 ), and these fluorinated acrylate copolymers (n=1j 6 Sl, 41 ), and these fluorinated acrylates and the fluorinated methacrylate copolymers (
n = 1.36 Sl, 41), and these heptafluorinated acrylate, heptafluorinated methacrylate, and methyl methacrylate copolymers (n = 1.37-1.45), represented by the general formula 〇H2 = 0F-1coOR''f Polymers and copolymers based on 2-fluoroacrylate (n=1.37S1.42), where n"r:
OH,, (OH7)ln(CF2)n2%(OH2)m
(OF2)nH, 0H2CF2CHF OF,,c<a
Examples include y, )2, fluorine-containing alkyl 7-maric acid ester polymer (n=1.50 to 1.42), and the like.

The difference between the refractive index n of the core component polymer forming the island component of the multi-optical fiber of the present invention and the refractive index n2 of the sheath component or sea component polymer is 0.01 or more. This is also necessary in order not to increase the transmission loss of light transmitted through the components. In the case of multi-optical fibers made of combinations with n, -n2 values as small as 0.01, a phenomenon in which light introduced into the core component leaks to the sheath layer is observed, and the method of the present invention In multi-optical fibers, the clarity of the transmitted image is significantly reduced.

FIG. 2 shows a cross-sectional view of an example of a spinneret used to efficiently produce the high pixel count plastic multi-optical fiber of the present invention. In the figure, (1) is a core forming cap;
21 is a cap for forming a set, (3) is a cap for forming a sea component, (4
) is the nozzle for distributing each component, (51° +61, +71 is the core component polymer supply port, sheath component supply port, sea component supply port D, (1a) is the nozzle for forming the core, (2a) is the nozzle for forming the sheath. , (3a) is a nozzle for forming a sea, and its lower end is characterized by a trumpet-shaped opening. (6b) and (7b) are nozzles for forming a sea, respectively. and a slit that regulates the flow of the sea component polymer flow.

The light guide having a three-layer structure spun from C5 is then aggregated by a collective nozzle with a substantially rectangular cross section, so that the outermost layer forms a sea part and the high part is arranged in a stacked bale arrangement. In addition, a multi-optical fiber having a cross-sectional structure as shown in FIG. 1 can be obtained. An example of the lateral shape of a multi-optical fiber made by the method described above is shown in a t-it diagram. The multi-optical fiber used in the present invention has a substantially rectangular cross-sectional outer circumferential shape, and its main feature is that each side has a concavo-convex shape formed by forming a stacked bale arrangement structure of optically transmitting island components. In addition, since the arrangement shape of the island components is a stacked bale structure, the shape can be kept approximately circular, and the image transmission performance can be excellent and the resolution can be high.

In the present invention, a multi-optical fiber assembly of the present invention can be obtained by joining a plurality of multi-optical fibers having the above-described structure so that the concave-convex structures on each side mesh with each other as shown in Figure 5) or (61). (52) , (5
4) are the respective protection parts. Therefore, as shown in Fig. 4, an enlarged cross-sectional view of the joint part, the mating surfaces (42) of the multi-optical fibers (41) have concave and convex surfaces that are effectively engaged with each other, resulting in good image transmission and resolution. A high-resolution multi-optical fiber assembly with 2 line pairs/parrot or more can be obtained.

The configuration of multi-optical fibers can be a rectangular laminated structure as shown in FIG. 3 (LIK) or a horizontally laminated structure as shown in FIG. 3 (BL).

Actual number below? The present invention will be explained in more detail by IJ.

Example Using a spinneret with a cross-sectional structure as shown in FIG. 2 and a spinneret with nine holes shown in Table 1, polymethyl having a refractive index of 1.492 and a melt flow rate of 1.2 was used as the polymer for forming the core component. methacrylate, a polyfluorinated methacrylate with a refractive index of 1,415 and a melt flow rate of 6 as the sheath-forming polymer, and a vinylidene fluoride copolymer with a melt flow rate of 12 as the sea component, and each lil! A multi-optic fiber gold with j prime number was obtained.

Each multi-element fiber t shown in Table 1 - number of pixels approximately 30,
A multi-optical fiber assembly was fabricated by stacking the fibers so as to have 000 pixels, and the characteristics thereof were investigated and are shown in Table 1. The multi-optical fiber assembly of the present invention had extremely good resolution at the joint of the multi-optical fibers.

[Brief explanation of the drawing]

FIG. 1 is an enlarged cross-sectional view of the multi-source fiber of the present invention, and FIG. 2 is a cross-sectional view of a composite spinning nozzle that can be usefully used to produce the multi-source fiber of the present invention. Figure 3 ta+
and (k)l are examples of cross-sectional views of the multi-optical fiber assembly of the present invention, and FIG. 4 is an enlarged cross-sectional view of the multi-source fiber junction of the multi-optical fiber assembly of the present invention. Patent applicant Mitsubishi Rayon Co., Ltd. Representative Patent Attorney 1) Takeshi Mura Figure 2

Claims (3)

[Claims] (1) 50 to 1000 optically transmitting islands with a diameter of 10 to 200 μm and a cross-sectional shape of approximately circular shape are arranged in the sea area, and the arrangement is in a substantially uniform bale arrangement. The cross-sectional shape of the multi-optical fiber is approximately rectangular, and each side thereof is configured with an uneven shape that reflects the cross-sectional shape of the light transmitting island and the stacked shape thereof. 1. A multi-optical fiber assembly, characterized in that a large number of plastic multi-optical fibers are stacked together so that the uneven shapes on the outer periphery of the multi-optical fibers are interlocked with each other. (2) The multi-optical fiber assembly according to claim 1, wherein the arrangement density of the island components is 23 inches/mm or more. (3) Both ends of a multi-optical fiber assembly with a substantially rectangular cross section are
The multi-optical fiber assembly according to claim 1 or 2, characterized in that the uneven surfaces of the multi-optical fibers are interlocked and stacked in several stages and rows in the form of bales.